How to Grow a Potted Five-Needle Pine? A Detailed Guide to the Latest Care Methods

The five-needle pine is also known as the Japanese five-needle pine, five-fork pine, and Japanese white pine, among other names. It is an evergreen coniferous tree of the genus Pinus in the family Pinaceae, named for its five needles growing in clusters. The plant is relatively short, grows slowly, has short needles and dense branches, an elegant posture, and a beautiful tree form. It is often used as a superior tree species for making bonsai, and its bonsai are now commonly cultivated throughout China. Let us take a look below at how to grow a potted five-needle pine!

Growth Habits of the Five-Needle Pine

There are many cultivars of the five-needle pine, and the Daban pine, which has the shortest needles (needle length about 2 cm) and dense branches, is the most precious. It likes a warm and humid environment and is a light-loving tree species with very high light requirements. The planting soil must not become waterlogged and must have good drainage and aeration; it grows poorly in damp, shady places. Although it has strong resistance to sea breezes, it is not suitable for growing in sandy soil. For fertilizing, organic fertilizer is best.

Propagation Methods of the Five-Needle Pine

1. Sowing: Sowing of the five-needle pine is carried out from March to April. The seed coat is thick and hard, making germination difficult, so 40 days before sowing, first treat the seeds with warm water at about 50 degrees for 3 to 4 hours, then remove them, mix them evenly with 2 times their volume of wet sand, and stratify them in sand to promote germination, then sow them in a seedbed. They can germinate after 20 to 30 days. In China, the five-needle pine rarely produces seeds and the seed germination rate is low, so grafting is mostly used for propagation.

2. Grafting: For the five-needle pine, both cut grafting and side grafting can be used, with side grafting being more common. It is usually carried out from the time sap begins to flow until before buds sprout, generally from late February to early to mid-March. The rootstock is chosen from 2-year-old robust black pine, and the scion is chosen from 1- to 2-year-old thick branches or buds. The grafting cut should be as close to the root as possible. After grafting, it should be placed in a semi-shaded place. If the scion's buds gradually turn green and begin to sprout, it indicates that the scion has healed.

3. Cutting: Cutting propagation of the five-needle pine is usually carried out in spring and autumn. Use 1-year-old branches and cut them into heel cuttings. After cutting, under conditions of shading and maintaining relatively high air humidity, roots can form after 70 to 80 days. After the cuttings have rooted, gradually increase light intensity and ventilation time so they gradually adapt to the external environment.

How to Grow a Potted Five-Needle Pine?

1. Soil: The potting soil for the five-needle pine should be sandy soil with good drainage and aeration, rich in organic matter, and slightly acidic. Black mountain soil, peat soil, and artificial media are preferable. A common mix is leaf mold, yellow soil (or black mountain soil), and sandy soil blended in a ratio of 6:3:1. The potting soil must not be alkaline, otherwise growth will be unfavorable and the five-needle pine will turn yellow and shed.

2. Light: The five-needle pine is a strongly sun-loving plant. Usually the pot should be placed in a dry, ventilated, sunny place for care; excessive moisture or shade is unfavorable to its growth. Generally, for potted five-needle pine seedlings 1 to 2 years old, apart from appropriate shading at noon during the hot summer to prevent excessive sun exposure of the needles and cause scorched needles, at other times they should be placed outdoors in the open to fully receive sunlight.

3. Watering: The five-needle pine likes dryness and fears moisture. Watering should be moderate, and overwatering must be avoided; the foliage should be sprayed with water frequently. Soil moisture should be 15 to 30%. Generally, water once every 2 to 3 days in spring and once every 1 to 2 days in autumn. In summer, water once every morning and spray the foliage once in the evening. In winter, water once a week, and usually spray the foliage with clean water frequently.

4. Fertilizing: For the five-needle pine, it is best to use the method of light fertilizer applied sparingly, preferably fully decomposed cake fertilizer. Fertilizing mature plants should be done in spring and autumn. Spring fertilizer should be applied 2 to 3 months before sprouting, once every 10 days, at a concentration of about 15%, to promote sprouting and branch growth. In July and August, when the weather is hot, apply 10% dilute fertilizer water about once every half month, and apply it in the morning or evening.

5. Pruning: The five-needle pine needs continuous pruning to make its form increasingly perfect. Pruning branches is best done during the dormant period from December to January of the following year, mainly cutting off leggy branches, messy branches, and branches affected by pests and diseases. After pruning, seal the wounds with lanolin or adhesive tape to prevent resin bleeding. Bud pinching is generally done between April and May, and it is best to pinch buds when they have developed to 2 to 3 cm. Overlong buds on the tips of branches can be pinched off by 1/3 to 1/2 to avoid producing leggy branches, making the needles dense and short and the branches sturdy.

6. Repotting: When first potting the five-needle pine, it is best to use an unglazed clay pot because of its good aeration, which makes it easier to survive. After it has settled in the pot, switch to a purple clay pottery pot with an antique form and deep color. The potting soil should be changed once every 3 to 4 years, and the best time for changing the soil is from late February to early April or from September to mid-October. When repotting, some old roots should be appropriately pruned, and water should be watered thoroughly.

7. Pests and diseases: If not cared for properly, the five-needle pine is susceptible to leaf blight, pine needle cast, pine tip moth, scale insects, and other pests and diseases. Once discovered, diseased leaves should be removed promptly, and a 50% thiophanate-methyl wettable powder 800-fold solution should be sprayed. If scale insects or pine tip moths are found, an 80% pyrethroid insecticide diluted 1000-fold with water can be sprayed for control.